Denture teeth are well known in the art, there being many providers of such teeth. In addition, there are many patents disclosing denture teeth, a few of the U.S. patents being U.S. Pat. Nos. 1,657,673, 2,741,845, 3,755,898, 4,194,288, 4,208,794, 4,226,592, 4,445,863, 4,795,345, 4,969,817, 4,997,373, 5,326,262, 5,501,598, 5,951,289, 6,273,723, and Des. 374,288 to name just a few.
Furthermore, the literature is replete with various recommendations for posterior denture tooth forms primarily based on the functional requirements of mastication and stability of the denture base. The time-honored message has been “the flatter the ridge, the flatter the cusp angles”. There seems to be some logic to this statement, as several studies have given this concept some validity by reporting greater denture base distortion during function with steeper cusp angled teeth. Deductive reasoning could conclude that greater denture base movement would result in more soft tissue stress, which would eventually cause accelerated alveolar bone resorption.
In 1941, S. H. Payne, in Volume 47, pp. 20-22 of DENTAL DIGEST, reported on the “modified posterior set-up” of Dr. Edison J. Farmer. This occlusal scheme consisted of prominent maxillary lingual cusps that occluded with relatively flat and uncomplicated mandibular occlusal surfaces. Only the maxillary lingual cusps were in contact with the mandibular teeth. The forces of occlusion were transferred lingual to the mandibular ridge, thus the origin of the term “lingualized occlusion.” More recently, the term was changed to “lingual contact occlusion” so that it would not be confused with the suggestion that the teeth are set more lingual to the lower ridge, which can crowd the tongue space. This concept of denture occlusion has gained in acceptance through the years primarily because of its esthetics, biomechanics, simplicity, and favorable patient acceptance. Although the denture tooth debate continues, there does seem to be significant justification for the growing trend toward “lingualized (lingual contact) occlusion”. There are many biomechanical, clinical, and technical advantages of this occlusal scheme.
Quite simply put, it has been stated in the literature, “Lingualized (lingual contact) occlusion is an attempt to maintain the esthetic and food-penetration advantages of the anatomic form while maintaining the mechanical freedom of the non-anatomic form”.
Traditionally, in order to achieve the lingual contact occlusion concept one would need to mix and match denture teeth from different sets that do not share the same occlusal morphology and facial contours. This may result in the need for excessive tooth modifications. It may also compromise esthetics.